!important in CSS forces a style to apply regardless of cascade or specificity, making it override other styles even with higher specificity or later order; 1. Use it only in specific cases like overriding third-party inline styles, working in restricted environments, or temporary debugging; 2. Always place !important after the property value and before the semicolon, as it applies only to that single declaration; 3. To override !important, use a more specific selector with !important or a later rule with equal/higher specificity; 4. Avoid using it as a quick fix for specificity issues, as it indicates poor CSS structure; 5. Best practices include avoiding !important in reusable code, improving selector logic, using CSS custom properties or utility frameworks, and inspecting styles with developer tools—refactor CSS first, use !important only as a last resort.
Using !important
in CSS is straightforward, but it should be done carefully because it overrides the natural cascade and specificity of styles, which can make your CSS harder to maintain.

What !important
does
When you add !important
to a CSS declaration, it forces that style to be applied, regardless of the order of rules or selector specificity.
.element { color: blue !important; }
In this example, the text color will be blue—even if another rule later in the stylesheet sets a different color, or if a more specific selector tries to change it.

When to use !important
You should avoid using !important
in most cases. But there are a few legitimate scenarios:
- Overriding inline styles from third-party code (like ads or widgets).
- Working in environments where you can't edit the source CSS (e.g., browser extensions or user styles).
- Quick debugging or testing (but remove it before production).
?? Never use
!important
as a quick fix for specificity issues—it’s a sign your CSS structure needs improvement.
How to use it correctly
Place !important
after the value of a property, right before the semicolon:
p { font-size: 18px !important; margin: 0 !important; background: red !important; }
It only applies to that one declaration—not the whole rule block.
How to override !important
If you must override a style that uses !important
, you have a few options:
- Use another
!important
rule with a more specific selector:#specific-id p { color: green !important; }
- Or use the same or higher specificity later in the stylesheet:
/* This will win if it comes after the previous rule */ body .element { color: green !important; }
Even with
!important
, source order still matters when specificity is equal.
Best practices
- ? Don’t use
!important
in reusable components or libraries. - ? Fix the root cause: improve selector specificity or restructure your CSS.
- ? Use CSS custom properties or utility-first frameworks (like Tailwind) to avoid conflicts.
- ? Use developer tools to inspect why a style isn’t applying—often a better solution exists.
In short:
!important
is a tool of last resort. Use it sparingly, and always consider refactoring your CSS first.The above is the detailed content of how to use !important in css. For more information, please follow other related articles on the PHP Chinese website!
- ? Don’t use

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